1. Field of the Invention
The present invention, in general, relates to golfing apparatus and, more particularly, to devices used by golfers to indicate the direction to putt a golf ball whilst on the putting green.
Devices to assist golfers putt are well known. However they require the user to tilt the device back and forth while simultaneously aligning various longitudinal and transverse line between the cup, the ball, and the slope of the green in order to determine the direction to putt.
For certain devices, the user must "guess" the average slope of the green that exists between the ball and the cup and then align transverse lines of the device with the estimated inclination of the average slope. Any error in the determination of the slope by the golfer will affect the reliability of the device being used.
Accordingly there exists today a need for a device that easily provides a sight trajectory by which a golfer can attempt to direct the shot (putt) in the direction provided by the device whilst automatically determining, and thus correcting for, the slope of the green.
2. Description of Prior Art
Golf putting devices are, in general, known. For example, the following patents describe various types of these devices:
U.S. Pat. No. 3,870,299 to Howe, Mar. 11, 1975;
U.S. Pat. No. 4,258,475 to Buckley, Mar. 31, 1981;
U.S. Pat. No. 4,260,151 to Weaver, Apr. 7, 1981;
U.S. Pat. No. 4,984,791 to Labell, Jan. 15, 1991; and
U.S. Pat. No. 5,052,114 to Levenson et al, Oct. 1, 1991.
While the structural arrangements of the above described devices, at first appearance, have similarities with the present invention, they differ in material respects. These differences, which will be described in more detail hereinafter, are essential for the effective use of the invention and which admit of the advantages that are not available with the prior devices.